Sunset Mock-Mirage

Michiel de Boer (site) captured this miraged sunset near Beverwijk in The Netherlands. The montage combines four stages. A temperature inversion layer, clearly visible in the image, created the mirage.

©Michiel de Boer, shown with permission.

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One star � many suns.

A bright oval sun sinks into a dark atmospheric band. Inside the band are solar pancakes ever changing their shape. Eventually the topmost sun disappears altogether leaving only the pancakes. Then the darker band itself empties as the pancakes thin and migrate to its top and bottom.

The classical 'mock-mirage' has three suns. The first, above the dark layer, slides downwards. The layer appears to obscure the sun's lower edge giving the appearance of a sunset at a false horizon. This image seems to be the �real� one but the second and third suns are no less real.

The second sun is wholly within the layer and thus is only seen as a slice. A fortuitously placed sunspot would reveal it as inverted. It rises as sunset progresses.

The third image , also within the layer, is upright and sinks.

The mirage forms during temperature inversions � unusually cooler air beneath warmer. The almost horizontal setting sun rays refract at the temperature/density gradients and curve to appear to come from new directions.

Michiel de Boer�s mirage is richer than the above. There are at least three rather than two images in the main inversion layer. Two images are above the layer and the topmost sun is strongly flattened. The temperature profile was complex with several inversion kinks.

Mock-mirages generate small short-lived green flashes on the uppermost solar limb. They are frequently photographed but do not hazard eyes by searching visually.

The three images of a classical mock-mirage sunset